Your heart has four valves that keep blood flowing in the correct direction. These valves include the mitral valve, tricuspid valve, pulmonary valve and aortic valve. Each valve has flaps (cusps or leaflets) that open and close once during each heartbeat. Sometimes, the valves don't open or close properly, disrupting the blood flow through your heart and potentially impairing the ability to pump blood to your body.
In aortic valve regurgitation, the valve between the lower left heart chamber (left ventricle) and the main artery that leads to the body (aorta) doesn't close properly, which causes some blood to leak backward into the left ventricle. This forces the left ventricle to hold more blood, possibly causing it to enlarge and thicken.
At first, left ventricle enlargement helps because it maintains adequate blood flow with more force. But eventually these changes weaken the left ventricle â and your heart overall.
Any condition that damages a valve can cause regurgitation. Causes of aortic valve regurgitation include:
Congenital heart valve disease. You may have been born with an aortic valve that has only two cusps (bicuspid valve) or fused cusps rather than the normal three separate cusps. In some cases a valve may only have one cusp (unicuspid) or four cusps (quadricuspid), but this is less common.
These congenital heart defects put you at risk of developing aortic valve regurgitation at some time in your life. If you have a parent or sibling with a bicuspid valve, it increases the risk that you may have a bicuspid valve, but it can also occur if you don't have a family history of a bicuspid aortic valve.
- Age-related changes to the heart. Calcium deposits can build up on the aortic valve over time, causing the aortic valve's cusps to stiffen. This can cause the aortic valve to become narrow, and it may also not close properly.
- Endocarditis. The aortic valve may be damaged by endocarditis â an infection inside your heart that involves heart valves.
- Rheumatic fever. Rheumatic fever â a complication of strep throat and once a common childhood illness in the United States â can damage the aortic valve. Rheumatic fever is still prevalent in developing countries but rare in the United States. Some older adults in the United States were exposed to rheumatic fever as children, although they may not have developed rheumatic heart disease.
- Other diseases. Other rare conditions can enlarge the aorta and aortic valve and lead to regurgitation, including Marfan syndrome, a connective tissue disease. Some autoimmune conditions, such as lupus, also can lead to aortic valve regurgitation.
- Trauma. Damage to the aorta near the site of the aortic valve, such as damage from injury to your chest or from a tear in the aorta, also can cause backward flow of blood through the valve.